The behemoths are already based upon open source tech and have contributed to it. But what they make on top of it neither has its "schema" (software sufficient

The behemoths are already based upon open source tech and have contributed to it. But what they make on top of it neither has its "schema" (software sufficient to fork your own) open nor the instances accessible or communicatable. The same way that installing Linux doesn't mean I can access your files or configurations on top of them. The way I see it that is a price of open source software that you can't control how others use it in exchange for not being controlled. Open standards as positive externalities would be a rational reason for tax discounts even if the value of it varies greatly - although good for repairs few would care for a specific printer model's firmware as it is so specific in its domain.